Temperature-regulating means for liquid-cooled engines



April 24. 1928.

W. H. DRISCOLL TEMPERATURE'REGULATING MEANS FOR LIQUID COOLED ENGINES Filed June 18, 1927 Patented Apr. 24, 1928.

' combustion UNITED STATES PATENT OFFICE.

WILLIAM H. DRISC'OLL, OF JERSEY CITY, NEW JERSEY.

TEMIPERATURE-REGULATING MEANS FOR LIQUID-COOLED ENGINES.

Application filed June 18, 1927. Serial No. 199,728.

This invention relates to liquid cooled en- 'gines and has for itsprincipal object the provision of means for raising and otherwise regulating the temperature of thecool ing liquid so as to keep-the same from free;- ing during cold weather and also to facilitate the starting-of the engine after a rest period during which the cooling liquid may have reached a temperature lower than desirable.

Hide my invention is capable of use in connection with any liquid cooled engine, it-

is particularly applicable to the ordinary ,engine used in automobiles and other motof' vehicles.

A vast amount of study and work has been spent on the problem of keeping combustion engines'properly cooled and at the present time these efforts seem to have succeeded in producing eflicient radiation and cooling sys tems which safeguard, the engine from the danger of overheating. But there is anotherphase of the combustion engine problem, and particularly the motor vehicle problem, which has up to the present time remained unsolved; to wit, the problem of preventing the cooling water or other liquid from freezing or approaching the freezing point after the engine or motor vehicle carrying the engine has been idle for a period in cold weather.

Heretofore owners and users of motor vehicles have sought to partially safeguard against the possibility of freezing by mixing with the cooling water some liquid having a lower freezing point such as alcohol. This expedient, of course, partially offsets the danger of freezing, but only partially. Furthermore, it has the disadvantage that it is very easy to forget to add the alcohol at the proper time, or if not forgotten, it may be unavailable when needed.

My invention proposes the use of a heat-.

ing element (in the preferred embodiment an electric heating element) which may be inserted at some point in the cooling system,-

be maintained at a satisfactory temperature. Other objects and advantages to be de rived from the use of,the novel features of this invention reside in the specific combination and arrangement of the parts. Others will become obvious from an inspection of the following description when read with reference to the accompanying drawings, wherein the preferred embodiment-is illustrated and wherein like reference characters refer to like parts in the different views.

In the drawings l igqre 1 is a front eleva tion view of a common type of radiator used inconnection with the coolingof automotive engines, with the position occupied by my novel apparatus indicated.

Figure 2 is a side view of the radiator and the parts shown in Fig. 1.

Figure 3 is a larger view element indicated in Fig. 1.

Figure 4 is an elevation view, partly in section, of the preferred .form of automatic controlling switch.

Figure 5 is a schematic representation of the preferred electrical hook-up.

Figs. 6 and 7 are modifications of the de-.

vice shown in Fig. 4.

Referring to Fig. 1, reference character 1 indicates a radiator, such as is commonly used on automotive vehicles for the function of providing an exposed radiating surface in the path of'the circulating cooling liquid. As shown the radiator l-carries a multiplicity of square tubes 2' through which the atmospheric air passes, the circulating cooling liquid passing between the tubes-or the arrangement may be reversed. As the cooling liquid circulates in the water jacket of the engine (not shown) it the combustible charge inthe engine and then flows to the radiator 2 where the heat previously absorbed is transferred to the atmosphere through tlieinstrumentality of the radiator as the liquid courses downwardly around the tubes and into the bottom compartment 3, from which point it returns to the engine jacket either by means of a pump or by so arranging the circuit that the exof the heating absorbs heat from.

pansion of the liquid by the heat absorbed in the jacket and its consequent tendency to rise causes it to circulate with -suflieient-rapidity.

' I propose to insert, preferably in the hottom compartment ,3 (but not necessarily'in this location) a heating unit 4, which may be permanently mounted in place in the raof the preferred construction, the heating 'unit 4 Comprises a casing 6 of suitable heat transmitting material (and preferably noncorrosive also) such as brass or nickel for example. \Vithin the casing 6 is a non-conducting core 7 on whichvis wound one or more high resistance filament wires 8 suitably insulated at all points and connecting with the terminals on base 5, so as to receive electric current when a circuit is closed to v socket 6' and base 5.

the year;

With the provision of the elements just described, and by utilizing suitable current transmitting means (such as a pair of leads 9 and 10 tapped into feed lines 11 and 12), heat may be applied to the liquid in radiator 2 by direct conduction-through casing (3. The'heat thus transmitted to the liquid will pass by convection to all portions of the circulating system, thereby preventing the liquid from freezing or desirably low temperature while the engine, or vehicle carrying the engine, is standing idle in a cold place, such as is usual in many garages and storerooms in the cold season of Of course the heating unit 4 is constructed so as to supply substantially the desired amount of heat, but additional regulation of the heat supply may be provided by placing a clock or other time-controlled circuit-controlling switch in the circuit from feed lines 11 and 12 to the heating element 4. Such a switch may be set to interrupt or close. the circuit at any pre-determined hour. Another means of regulation is by the tempera ture of the circulating liquid. Such a means is illustrated in Fig. l, where a thermostatically-controlled switch is shown at 13 mountedin a housing 1% secured to the inner side of wall 15 of radiator 1.

As shown in Figure i, theswitch 13 is operable by a thermal unit 17 having suitably high coefficient of expansion. This thermal unit 17 is shown exposed to the liquid inthe compartment 3 of radiator 1, so as to cause movement of the rod 18 in response to changes in' the temperature of the liquid. Movement of rod 18 a suificient distance to the left, as shown, throws the two arms of switch 13 (with the assistance of spring 19) away from terminal blocks 20 1 and 21, and movement a sufiicient distance dropping to an unnular spring 38 located in the carriage When this condition occurs it is obvious that assesses and serving for the attachment of a. plug 22 connected with lead 9 in the manner suggested in Figure 1. 'With this arrangement (whichmay be varied in forni'and construction, if desired) the engine may be left with the circuit to the heating element closed at both socket 6 and socket 22, in which event the energization of the heating element will depend upon the'operation of switch 13, which in thermal unit 17 lhus an automatically regulable system is provided which will maintain the liquid at a without any attention on the part of the user beyond theuinitial act of inserting the lead plugs in the socket 6 and 22;

It may be noted that suitable means, as gasket 25 and stufiing box 26, are provided for keeping the switch housing 14 free from moisture.

Figures 6 and 7 illustrate a modified construction which might be used for providing desired temperatue turn is governed by the thermostatic control of the system in lieu of the construction shownin Figure 4. This modification comprises a bellows 30 suitably mounted in'a housing 31 secured to the wall 15 of the radiator and having formed on one side thereof an elongated tubular element 32, so disposed as to extend into the liquid compartment of the radiator and constructed of a suitable heat transmitting material;

of liquid therein and also against the walls of the bellows 30. lhe pressure thus set up will tend to move the outer wall of the bellows against the tension of spring 35, thereby causing a movement of the pin 36 to the left. Nhen this pin 36, as shownin Figure 7, has, due to the force thus exerted against it, moved a suilicient distance to the left, the enlarged central portion on the hub 37, which forms a continuation of the pin 36, will have reached a position opposite the anthe spring 38 will, because of its tension, snap to the opposite side of the chamber 40, carrying with it the carriage 39. The carriage 39 may be equipped with the bridging member 41 which may serve as a circuit making and breaking means to bridge suitable terminals co. .iecting with the leads 42 and 43 shown in Figure 6. lVith this con-' struction it will be apparent that an alternate making and breaking of the circuit thru leads 42 and &3 can be effected in response to the reciprocation of bar 36 and hub 37, said bar and hub being in turn actuated by the alternate expansion and contraction of the outer wall of bellows in response to the differences in-tempcrature of the liquid therein.

It is to be understood that other changes in the construction, arrangement. and com bination of the parts may be made without departing from the scope of this invention as described herein and as defined in the appended claims.

I claim:

1. In an engine cooling system comprising a radiator, a housing mounted on the shell of the radiator, contact members in said housing, a switch in the housing adapted to bridge said contact members. means in the lows. compartment of the radiator and directly responsive to temperature changes "of the liquid therein for opening and closing said switch, a heating unit in the lower compartment of the radiator mounted on the radiator shell and means for establishing a circuit through the heating unit, the contact members and a source of electrical energy.

2. In an automobile radiator, means for regulating the temperature of the cooling liquid therein comprising a heating unit mounted in the lower compartment of the radiator, means for establishing an electric circuit from a source of electrical energy to said heating unit, a make and break device in said circuit consisting of a housing mounted on the radiator shell, contact members in said housing, a snap switch in the housing adapted to bridge said contact members, an element having flexible walls directly responsive to temperature changes of the liqnid within the radiator, and means connecting said element to the switch.

, Signed at Jersey City, N. J. this 17th day of June, 1927.

WILLIAM H. DRISCOLL. 

